rs780625433

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PVS1PP3PP5_Very_Strong

The NM_000275.3(OCA2):​c.131del​(p.Gly44GlufsTer58) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,613,328 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

OCA2
NM_000275.3 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: -1.21
Variant links:
Genes affected
OCA2 (HGNC:8101): (OCA2 melanosomal transmembrane protein) This gene encodes the human homolog of the mouse p (pink-eyed dilution) gene. The encoded protein is believed to be an integral membrane protein involved in small molecule transport, specifically tyrosine, which is a precursor to melanin synthesis. It is involved in mammalian pigmentation, where it may control skin color variation and act as a determinant of brown or blue eye color. Mutations in this gene result in type 2 oculocutaneous albinism. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 17 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 15-28081743-TC-T is Pathogenic according to our data. Variant chr15-28081743-TC-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 521067.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
OCA2NM_000275.3 linkuse as main transcriptc.131del p.Gly44GlufsTer58 frameshift_variant 2/24 ENST00000354638.8

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
OCA2ENST00000354638.8 linkuse as main transcriptc.131del p.Gly44GlufsTer58 frameshift_variant 2/241 NM_000275.3 P1Q04671-1
OCA2ENST00000353809.9 linkuse as main transcriptc.131del p.Gly44GlufsTer58 frameshift_variant 2/231 Q04671-2
OCA2ENST00000431101.1 linkuse as main transcriptc.131del p.Gly44GlufsTer58 frameshift_variant 2/73
OCA2ENST00000445578.5 linkuse as main transcriptc.131del p.Gly44GlufsTer58 frameshift_variant 2/63

Frequencies

GnomAD3 genomes
AF:
0.0000657
AC:
10
AN:
152160
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000204
AC:
5
AN:
245200
Hom.:
0
AF XY:
0.0000224
AC XY:
3
AN XY:
133634
show subpopulations
Gnomad AFR exome
AF:
0.000324
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461168
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
726894
show subpopulations
Gnomad4 AFR exome
AF:
0.0000896
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000657
AC:
10
AN:
152160
Hom.:
0
Cov.:
33
AF XY:
0.0000673
AC XY:
5
AN XY:
74330
show subpopulations
Gnomad4 AFR
AF:
0.000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000945

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tyrosinase-positive oculocutaneous albinism Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingJohns Hopkins Genomics, Johns Hopkins UniversityJul 15, 2022This OCA2 variant (rs780625433) is rare (<0.1%) in a large population dataset (gnomAD: 6/276568 total alleles; 0.002%; no homozygotes) and has been reported in ClinVar. This frameshift variant (p.Gly44fs) in exon 2 of 24 results in a premature termination signal likely leading to nonsense-mediated decay and lack of protein production. Bioinformatic analysis predicts the co-occurrence of this variant on the same haplotype as c.1103C>T, although this has not been confirmed experimentally to our knowledge. We consider c.131del to be pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineApr 02, 2017The p.Gly44GlufsX58 variant in OCA2 has not been previously reported in individuals with disease but has been identified in 0.045% (4/8956) of African chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org). Although this variant has been seen in the general population, its frequency is low enough to be consistent with a recessive carrier frequency. This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 44 and leads to a premature termination codon 58 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Biallelic loss of function of the OCA2 gene is an established disease mechanism for oculocutaneous albinism type 2. In summary, although additional studies are required to fully establish its clinical significance, the p.Gly44GlufsX58 variant is likely pathogenic based upon predicted impact to the gene. -
SKIN/HAIR/EYE PIGMENTATION 1, BLUE/NONBLUE EYES Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsMar 23, 2024- -
Inborn genetic diseases Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsJun 24, 2016- -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 24, 2024This sequence change creates a premature translational stop signal (p.Gly44Glufs*58) in the OCA2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in OCA2 are known to be pathogenic (PMID: 19865097, 21541274). This variant is present in population databases (rs780625433, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with OCA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 521067). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.54
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.54
Position offset: 5

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs780625433; hg19: chr15-28326889; API